/*
 * Copyright 2017 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.util.internal;

import java.lang.reflect.AccessibleObject;

public final class ReflectionUtil
{

    private ReflectionUtil()
    {
    }

    /**
     * Try to call {@link AccessibleObject#setAccessible(boolean)} but will
     * catch any {@link SecurityException} and
     * {@link java.lang.reflect.InaccessibleObjectException} and return it. The
     * caller must check if it returns {@code null} and if not handle the
     * returned exception.
     */
    public static Throwable trySetAccessible(AccessibleObject object)
    {
        try
        {
            object.setAccessible(true);
            return null;
        }
        catch (SecurityException e)
        {
            return e;
        }
        catch (RuntimeException e)
        {
            return handleInaccessibleObjectException(e);
        }
    }

    private static RuntimeException handleInaccessibleObjectException(
            RuntimeException e)
    {
        // JDK 9 can throw an inaccessible object exception here; since Netty
        // compiles
        // against JDK 7 and this exception was only added in JDK 9, we have to
        // weakly
        // check the type
        if ("java.lang.reflect.InaccessibleObjectException"
                .equals(e.getClass().getName()))
        {
            return e;
        }
        throw e;
    }
}
